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III. Match the words with their synonyms.



1. necessity a. grand

2. come to an end b. protect

3. pattern c. complete

4. plane d. basic

5. main e. need

6. fussy f. sample

7. great g. bustling

8. defend h. flat

IV. Match the words with their opposites.

1. mountainous a. add

2. deterioration b. create

3. first c. accelerate

4. unsteady d. flat

5. delay e. final

6. diminish f. improvement

7. ruin g. reliable

8. insecure h. stable

V. Fill in the prepositions.

1) to be drawn … sth; 2) a need … sth; 3) to succeed … sth; 4) to lead … sth; 5) to dig … sth; 6) … the search …; 7) to share the risk … sth.

VI. Insert the words from the list.

Techniques, combination, forced, mountain, notorious, railroad, long-distance, spectacular, succession, drainage, inflow

In the United States the first … tunnel was a 701-foot construction on the Allegheny Portage Railroad. Built in 1831-33 it was a … of canal and railroad systems carrying canal barges over a summit. Simultaneously more … railroad tunnels were being started through the Alps. Its engineer, A. Sommeiller, introduced many pioneering … . Ventilation became a major problem which was solved by the use of … air from water powered fans and a horizontal diaphragm at mid height. Most … rock tunnels have encountered problems with water inflows. One of the most … was the first Japanese Tanna Tunnel driven through the Takiji Peak in 1920. The engineers and crews had to cope with a long … of extremely large inflows the first of which killed 16 men and buried 17 others. Three years later another major … drowned several workers. In the end Japanese engineers hit on the expedient of digging a parallel … tunnel the entire length of the main tunnel. In addition, they resorted to compressed - air tunneling with shield and air lock a technique almost unheard - of in … tunneling.

FOLLOW UP ACTIVITIES:

Speak on:

The history of tunneling.

The history of tunneling in Belarus.

 

Unit 6: KINDS OF TUNNELS

Lead in

What are tunnels used for?

Find the following terms and memorize their meaning.

to bore steep grades to haul exhaust fumes fan jam to line to withstand blasting open cut cut and cover shield interference savings

Text 1. KINDS OF TUNNELS

Tunnels have many uses: for mining ores, for transportation—including road vehicles, trains, subways, and canals—and for conducting water and sewage. Underground chambers, often associated with a complex of connecting tunnels and shafts, increasingly are being used for such things as underground hydroelectric-power plants, ore-processing plants, pumping stations, vehicle parking, storage of oil and water, water-treatment plants, warehouses, and light manufacturing; also command centres and other special military needs.

There are four main types of tunnels. They are: (1) rail road tunnels, (2) motor-traffic tunnels, (3) water tunnels and (4) mine tunnels.

Railroad tunnels. Among the world's greatest engineering feats was the boring of long railroad tunnels through the rocks of the Alps and the Rocky Mountains. Railroad tunnels reduce traveling time and increase the efficiency of trains. The steeper a locomotive must climb, the less weight it can pull. Tunnels through mountains reduce steep grades, allowing trains to haul more goods and people.

Motor-traffic tunnels. These tunnelsprovide routes for automobiles, trucks, and other motor vehicles. Such tunnels have special equipment to remove exhaust fumes. For example, the Holland Tunnel, which is situated under the Hudson River and which links New York City and New Jersey, uses electric fans for ventilation. These fans are capable of completely changing the air in the tunnel every 90 seconds. Many motor-traffic tunnels also have signal lights and special monitoring systems to help pre­vent traffic jams.

Water tunnels.Many tunnels provide water to city waterworks, to hydroelectric power plants, or to farms for irrigation. Others carry storm drainage or sewage. Most water tunnels measure 10 to 20 feet (3 to 6 meters) or more in diameter, and they have smooth linings that help the water flow. Many tunnels carrying water to hydroelectric power plants are lined with steel to withstand extremely high water pressures.

Mine tunnels.Theseare made by blasting or by tunneling machines. Mine shafts are not usually lined, but they may have supports.

COMPREHENSION CHECK

1.Decide whether the following statements are true or false according to the text:

1. Tunnels are mainly used for transportation including road vehicles, trains, subways and canals.

2. Underground chambers serve different purposes.

3. There are 5 main types of tunnels.

4. The boring of long railroad tunnels through the rocks of the Alps and the Rocky Mountains was an outstanding feat.

5. Though railroad tunnels increase the efficiency of trains they don’t reduce travelling time.

6. The steeper a locomotive must climb, the heavier weight it can pull.

7. It is necessary for motor-traffic tunnels to be equipped with special equipment to remove exhaust fumes.

8. Electric fans for ventilation in the Holland Tunnel can completely change the air in the tunnel every hour.

9. Water tunnels provide water to city waterworks.

10. Mine tunnels are made by tunneling machines.

2. Answer the questions:

1. What are tunnels used for?

2. Why are underground chambers so widely used?

3. How many types of tunnels do you know?

4. What is one of the world’s greatest engineering feats?

5. Why do railroad tunnels increase the efficiency of trains?

6. What do motor-traffic tunnels provide?

7. How are exhaust fumes removed?

8. Why do motor-traffic tunnels have special signals and monitoring systems?

9. Where do tunnels carry water?

10. How are mine tunnels made?

LANGUAGE FOCUS

III. Insert the words from the list

bottom, shaft, rock, adjacent, underwater, trench, tunnel, chambers, horizontal, entrance

A tunnel is an essentially … underground passageway produced by excavation or occasionally by nature’s action in dissolving a soluble … . A vertical opening is usually called a … . True tunnels and … are excavated from inside. Then, they are lined to support the … ground. A hillside tunnel … is called a portal. Tunnels may also be started from the … of a vertical shaft or from the end of a horizontal …, driven principally for construction access and called an adit. Tunnels … are now commonly built by the use of an immersed tube. Long prefabricated tube sections are floated to the site, sunk in a prepared … and covered with backfill.

IV. Fill in the prepositions:

1. the efficiency … sth; 2) to provide sth … sth; 3) to be associated … sth; 4) to be situated … sth; 5) to be capable … sth; 6) … diameter; 7) to be lined … sth.

V. Complete the sentences using appropriate derivates of the words given on the right.

Tunnel is an underground passageway. Tunnels provide convenience

highways, subways and railroad with … routs past … and nature

artificial obstacles. … use tunnels to reach … minerals mine

value

deep within the earth. Some tunnels provide fresh water

for … or …, and others transport wastes in sewer systems. irrigate drink

In addition, tunnels provide underground space for cold … . store

VII. Make the precis of the text

Text 2. SUBWAY

Subway, also called underground, tube, or metro, underground railway system used to transport large numbers of passengers within urban and suburban areas. Subways are usually built under city streets for ease of construction, but they may take shortcuts and sometimes must pass under rivers. Outlying sections of the system usually emerge above-ground, becoming conventional railways or elevated transit lines. Subway trains are usually made up of a number of cars operated on the multiple-unit system.

There are three types of subways. One is called the open cut. The construction crew tears out the streets and builds the subways in deep ditches. If two lines are going to cross, the crew digs one roadbed deeper than the other. If the crew lays a pavement or other type of cover over the cut in the ground, the subway is called a cut and cover subway. The third form of subway, which is called a tube, is constructed by boring through the earth at the desired depth without disturbing the surface. This type of construction is for one or two tracks. The tunnels of an open-cut subway have a rectangular shape. The tunnels of a tube subway are usually circular or semicircular. New York City's subway is mainly rectangular. Much of the London subway is semicircular.

London's underground. The first subway system was proposed for London by Charles Pearson, a city solicitor, as part of a city-improvement plan shortly after the opening of the Thames Tunnel in 1843.

After 10 years of discussion, Parliament authorized the construction of 3.75 miles (6km) of underground railway between Farringdon Street and Bishop's Road, Paddington. Work on the Metropolitan Railway began in 1860 by cut-and-cover methods—that is, by making trenches along the streets, giving them brick sides, providing girders or a brick arch for the roof, and then restoring the roadway on top. On Jan. 10, 1863, the line was opened using steam locomotives that burned coke and, later, coal; despite sulfurous fumes, the line was a success from its opening, carrying 9,500,000 passengers in the first year of its existence. In 1866 the City of London and Southwark Subway Company (later the City and South London Railway) began work on their "tube" line, using a tunneling shield developed by J.I I. Greathead. The tunnels were driven at a depth sufficient to avoid interference with building foundations or public-utility works, and there was no disruption of street traffic. The original plan called for cable operation, but electric traction was substituted before the line was opened. Operation began on this first electric underground railway in 1890 with a uniform fare of two pence for any journey on the 3-mile (5-kilometre) line. In 1900 Charles Tyson Yerkes, an American railway magnate, arrived in London, and he was subsequently responsible for the construction of more tube railways arid for the electrification of the cut-and-cover lines. During World Wars I and II the tube stations performed the unplanned function of air-raid shelters. Today, London has 10 lines that provide quick, cheap transportation to all parts of the city and suburbs. This subway system is often called the tube or the underground. Some of its subway lines are so far underground that passengers go down on elevators. There are numerous escalators which help to keep the traffic moving. The first was installed in 1911. One of them at Leicester Square is over 80 feet in length. On long escalators the speed is changeable. The "up" escalator runs at full speed when carrying passengers, but when empty it runs at half speed. Many of the new escalators have automatic control making a more frequent service throughout the day possible.

Automatic trains, designed, built, and operated using aerospace and computer technology, have been developed in a few metropolitan areas, including a section of the London subway system, the Victoria Line (completed 1971). The first rapid-transit system to be designed for completely automatic operation is BART (Bay Area Rapid Transit). Air-conditioned trains with lightweight aluminum cars, smoother and faster rides due to refinements in track construction and car-support systems, and attention to the architectural appearance of and passenger safety in underground stations are other features of modern subway construction.

COMPREHENSION CHECK

1.Decide whether the following statements are true or false according to the text:

1. Subway is used to transport passengers from one city to another.

2. Subways are usually built under city streets and sometimes under rivers.

3. There are four types of subways.

4. The construction crew digs one roadbed deeper than the other if two lines are going to cross.

5. The subway is called a cut and cover subway if the crew lays a pavement under the cut.

6. The tunnels of a tube subway have a rectangular shape.

7. New York City’s subway is mainly semicircular.

8. In 1863 the City of London and Southwark Subway Company began work on their “tube”.

9. A uniform fare for any journey on the 3-mile line was two pence.

10. Some of the subway lines are rather far underground and passengers go down on elevators.

II. Answer the questions:

1. What is a subway?

2. How many types of subways are there?

3. When does the crew dig one roadbed deeper than the other?

4. What is the shape of an open-cut subway and a tube subway?

5. Who proposed the first subway system for London?

6. Why was the first line a success despite sulfurous fumes?

7. How were the tube stations used during world wars I and II?

8. When was the first escalator installed?

9. Why is the speed on long escalators changeable?

LANGUAGE FOCUS






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